It is known to provide harvesting machines with a chopping device in which the harvested crops, preferably stalky harvested crops such as maize or sugar cane, after being cut or detached from the ground during the harvesting process, are chopped and/or shredded in a further operating step. Such chopping devices are used, for example, in forage harvesters or even in sugar cane harvesting machines. The chopping devices may be configured as single or twin chopping drum devices, wherein the first chopping drum device comprises a rotating drum which is provided with blades and which rotates against a fixed blade, wherein the edges of the blades are aligned axially with a rotational axis of the drum and the harvested crops to be chopped are guided between the chopping drum and the fixed blade and thereby shredded. The second chopping drum device, however, comprises two chopping drums rotating in opposing directions and provided with blades, wherein the harvested crops to be chopped are guided between the two chopping drums and thereby shredded. In this case, the edges of the blades are also respectively aligned axially with the rotational axes of the drums. The rotational speed and also the number of blades arranged on a chopping drum may be varied, depending on the desired degree of chopping. In particular, in a twin chopping drum device, a fine adjustment of the drums relative to one another has to be carried out in order to ensure that the blades run against one another in a precise manner and accurately spaced apart. However, this is often only possible after assembling the harvesting machine and, in particular, after installing the chopping device. In said chopping device, one of the chopping drums is generally arranged after the installation thereof and/or after mounting in the drive chain so as to be non-adjustable, wherein the second chopping drum is configured to be releasable from the drive train and its position and/or rotational position is configured to be correspondingly adjustable relative to the other chopping drum. Generally, this is implemented via a releasable flange connection, screw connection or bolt connection between a drive wheel in the drive train of the chopping device and the chopping drum to be adjusted. The adjustment to be carried out and/or the so-called “timing” takes place in this case when the gear unit and/or housing of the drive train of the chopping device are open, which involves a certain mounting cost and loss of time. It is also known to avoid opening the gear unit and/or the housing of the drive train, by a clutch arrangement being provided on one of the chopping drums in order to permit a non-positive connection and/or a release of the clutch device from outside the gear unit and/or the housing of the drive train. A drawback here is that the known solutions provide the required non-positive connection for the clutch arrangement by a plurality of connecting bolts and/or screws which are arranged in a specific radius relative to the rotational axis of the chopping drum and as a result are subjected to high alternating bending stresses. Additionally, the screws are provided with screw heads, the distance thereof from the screw shank additionally providing points of application for alternating stresses due to bending moments. This may often lead to the fracture of the screw and thus cause the malfunction of the chopping device.
Therefore, it is desireable to provide a drive connection which permits a simple and practicable adjustment or tuning and/or “timing” of the chopping device and by which the aforementioned problems are overcome.